Hydraulic jack



C. F. BACON HYDRAULIC JACK April 18, 1933.

Filed Aug. 10, 1929 INVENTOR.

W; A T TOR N YS.

hmeaasr. 1a, 193:

U TED STATES PATENT OFFICE, y

r. moon, or m'rmnomfinamom, assrenoa r mums rams courm, or rams,uasaacnnsn'r'rs, a communion or mssacnusmrs HYDRAULIC JACK Applicationfiled August 10, 1829. Serial No. 884,927. I

This invention relates to hydraulic jacks. In general, an ob'ect of theinvention is to provide a hydraullc jack which is simple, sturdy andpermanent in construction, which is economical of manufacture,which canbe assembled and disassembled with extreme ease, and which is easy tooperate and which efliciently accomplishes the purposes for which it isintended. o A more specific object of the invention is to provide ahydraulic jack wherein the valves are so mounted that the -same may beinspected, cleaned, or replaced with especial ease, and which isparticularly sturdy in con- [5 struction.

Another object is to provide a hydraulic jack comprising a minimumnumberof conveniently situated parts.

Other objects of the invention will in part I) be obvious and will inpart appear hereinafter.

The invention accordingly comprises an article of manufacture possessingthe features, properties, and the relation of ele- 5 ments which will beexemplified in the article hereinafter described and the scope of theapplication of which will be indicated in the claims.

For a fuller understanding of the nature 0 and objects of the inventionreference should be ha'd'to the following detailed description taken inconnection with the accompanying drawing, in which:

Figure 1 is a partly sectional view of a 5 hydraulic jack embodying theinvention; 7

Fig. 2 is a detail view showing the relief valve in open position; and

Fig. 3 is an enlarged view of the valves and the associated structure.

0 In accordance with the invention, there is provided a hydraulic jackin which the intake, exhaust and relief valves are all assembled so asto be readily accessible for inspection or replacement, and at the same5 time to be operated with a maximum of ease on the part of the user.

In the exemplified jack, the valves are all mounted within the pumpbarrel so that the same may be removed upon the removal of 0 the pumpbarrel; and the relief valve so positioned as to be operated by thepump, thus permitting the piston to be lowered as well as raised by amovement of the pump handle,

The exemplified jack comprises an outer casing 9, the lower portion 10.of which provides a base for the 'ack. Within the casing 9 is acylindrical tu e 11 serving to-provide the outer walls of a pistonchamber or cylinder 12 and the inner walls of a fluid reservoir 13.Fitting in'the cylinder is a piston 14 on which a head 15 is suitablysupported,

as by a screw 16, whereby the height of the head may be adjustedbeforethe liftin operation is begun. At the upper end 0 the structureare nuts 17 and 18 which close the same and firmly unite the elements.The base 10 of the casing is formed, in the pres-' ent instance, with ascrew lu bore 20 communicating with aiore 21 in the base to provide apassageway 22 leading from the piston cylinder. The base'is also formedto provide a passageway 23 extending from the reservoir 13. in adirection above and parallel to the passageway 22, in the presentinstance. The base is extended laterally, as at 24, and the lateralportion thereof formed to provide a control chamber 25 communicatingwith the passageways 22 and 23 and arranged to receive a pump barrel 26which is removably secured to the lateral portion 24, as bymeans ofscrew threads 27. -At a point between the passageways 22 and 23 there isprovided a shoulder 28 against which the lower end of the pump barrel isadapted to rest. Within the pump barrel 26 there is provided a pumpplunger 29 the handle 30 of which is suitably mounte as by means of alink 31 which is pivotally connected to a lug 32 on the casing 9. Thepump barrel when screwed in fits tightly against the shoulder 28 so asto separate the 19 having a passageways 22 and 23; Communication betweenthese passageways is afforded by a channel 33 in the wall of the pumpbarrel, which, in the present instance, communicates with an annularchamber 34 surrounding the pump barrel and communicating with thepassageway 23. The bore of the pump barrel is narrowed intermediate itsends to provide a shoulder 35 serving as a chamber, an

at the botto m' of the umpstop for the gum is ared outwardl at its owerend to provide a bevelled shoul er 36 against fluid to be delivered tothe iston cylinder by the pump plunger, the re 'ef valve 37 istubular'in chamber from the reservoir 13, throng to the desired height.

cross-sectionto provide a channel 40 and is formed with openin s 41 toan annular chamber 42 commumcatin withthechannel 33, and control val esand 44 are provided in the channels 40 and 33. respectivel The ballvalves 43 and 44 .are preferab y pressed against suitable seats by meansof s rm i1 1 their respective cavities by ofiset portions 47 extendinginto recesses 48. It is to be observed that the ball valve 43 is carriedb the relief valve 37 and that access to bot of these valves can readilybe, had upon unscrewing the pump barrel and slipping the valve 37 fromthe bore thereof. Since the valve 44 prevents the passage of fluid-fromthe piston cylinder to the reservoir, the pump barrel is formed toprovide a channel 49 extending-from the bevelled shoulder 36 to theannular chamber 34, so as to .aflord communication between the piston clinder and the reservoir when the relief va ve is open.

Theoperation of the jack will be readily apparent from the foregoing.When the pump lunger is lifted the valve 44 will be open and fluid willbe drawn into the unlilp t e passageway 23, the annular chamber 34, thechannel 33, the annular chamber 42, the openin'gs 41, and channel 40.Upon the depression of the pump plunger, the valve 44 will close and thevalve 43 will be forced o n so as to force fluid from the ump cham rthrough the channel 40 and t e passageway 22 to the piston cylinder 12.Continuing the pumping operation the iston may be raised en it isdesired to lower the piston, all that is. necessary is to depress thepump plunger to a point where it contacts with the stem 39 and moves thesame downwardly, opening the relief valve 37 and permitting fluid toreturn from the piston cylinder through the passageway 22, the channel49, the annular chamber 34, and

passageway. 23 to the fluid'reservoir. Thus whenever it is desired tolower the jack, it is only necessary for theuser to press upon thehandle30 to operate the relief valve. When the jack has been loweredsufliciently, the user merely removes his hand from the handle, and thespring 38 acts to close the relief all that is nry is to unscrew the 45and 46, which are removably held valve When access to the valves isdesired,

barrel, whereupon ready access to th d valves can be easily obtained.

It will thus be seen that there is provided a hydrauhc Jack, which isnot only simple and sturdy in construction, but which can beoperated,'cleaned; or repaired with extreme ease.

. Since certain chan es may be made in the above article and di erentembodiments of the invention could be made without de arting from thescope thereof, it is intend that al matter contained in' the abovedescription or shown in the accompanying drawing shall be interpreted asillustrative and not in a limiting sense.

It is also to be-understood that the following claims are intended tocover all of the generic and s ific features of the invention hereindescri ,and all statements of the scope of the invention which as amatter of Ian age mightbe-said to fall therebetween. avlng described myinvention what I claun as new and desire to secure Patent is':

1. In ahydraulic jack, apiston cylinder, a piston therein, a reservoir,a passageway leadby Letters 'lng'from said piston cylinder, a passagewayleading from said reservoir, a ump barrel removab y secured on said jacand havin a pump chamber, said pump chamber being provided with but two.openings, a ump plunger permanently closing one of said opemn s, anindesendent member extending throug the secon of said openings andprovided with channeling, said channelin coma bore, the outer end ofwhic communicates with one of said p ways and the inner endof whichcommunicates with said chamber, the side wall of said pump barrel beingformed with a channel communicatingwith the other of said passagewa sand with said channeling, said member beiii g provided with a valvefor-closing the outer end of said bore and a valve normally closing saidchannel.

2. In a hydraulic jack, a" piston cylinder,

a piston therein, a reservoir, a passageway leading from said pistoncylinder, 9. passagewayleading from said reservoir, means mcluding apump barrel separating said as.- sageways, a pump plunger in said pumparrel, a relief valve carried in saidpump barrel and having a hollowstem affording communication between one of said passageways and thepump chamber, channels in said pump barrel and in the side of said stemafl'ording communication between the other of said passageways and thepump chamber, a control valve in said hollow stem, a control valve insaid channel in the pump barrel, and a channel in said pump barreladapted to connect said passageways when said relief valve is open.

3. In a hydraulic jack, a piston cylinder, a piston therein, areservoir, apassageway leading from said piston cylinder, a passagewayleading from said reservoir, means including a pump barrel separatingsaid assageways, a pumpplunger in said pump arrel, a relief valvecarried in the lower end of said pum'p barrel and having an upwardlyextending hollow stem affordingcommuof the plunger to its lowermostposition for moving said relief valve to open said channel connectingthe passageways.

4. In a hydraulic jack, a piston cylinder, a piston therein, areservoir,a passageway leading from said piston cylinder, a passage way leadingfrom said-reservoir, means including a pump barrel separating saidpassageways, saidpump barrel being removably mounted on the body of saidjack, a pump plunger in said pump'barrel, a relief valve carried in saidpump barrel and removable after the removal of said barrel and having ahollow stem affording communication between one of said passageways andthe pump chamber, channels in said pump barrel and in the side of saidstem affording communication between the other of said passageways andthe pump chamber, acontrol valve in said hollow stem, a control valve insaid channel in the pump barrel, and a channel in said pump barreladapted to connect said passageways when said relief valve is open.

5. In a hydraulic jack,a piston chamber, a reservoir, a pump barrelhaving a stepped bore, a pump plunger in the larger-diameter portion ofsaid bore, a valved channel formed in the side of the reduced diameterportion of said bore, a passageway leading from said reservoir andcommunicating with saidchannel, a passageway leading from the furtherend of said bore tosaid piston chamber, a

. channel connecting said passageways, a tubular relief valve in saidreduced-diameter portion of said bore'and adapted to close saidconnecting channel, means to normally maintain said relief valve inseated position, one end of said relief valve extending into the path ofsaid plunger when the relief valve is in seated position, and the wallof said relief valve being channeled to communicate with said valvedchannel, and valve means in the bore of said relief valve.

6. In a hydraulic jack, a piston chamber, a reservoir, aifiamber formedwith a recess,

a passageway leading from said piston chamber and communicating withsaid recess, passageways leading from said reservoir and communicatingwith said recess, a pump barrel having a cylindrical lower end extendinginto said recess and separating said assageways, a pump plunger in saidpump arrel, a valved channel in the wall of the cylindrical lower end ofthe pump barrel, said channelcommunicating with one of said passageways,a channel in the wall of said pump barrel adapted to connect saidpassageways one with another, a relief valve normally closing saidconnecting channel, said relief valve being formed to provide a channelcommunicating with said valved channel and with the other of saidpassageways and with the pump chamber, and a valve carried by 'saidreliefvalvefor selectively closing the channel therein.

7. In a hydraulic jack, a iston chamber, a reservoir, a pump cham er, apump barrel, a pump plunger, a passagewayconnecting said reservoir withsaid pump chamber, a valve for preventing movement of liquid from saidpump chamber tosaid reservoir, a assageway extending from said pistoncham er to said pump chamber, abypass connecting said passageways andcomprising a channel in said pump barrel and an exterior peripheralrecess in said pump barrel, a relief valve member normally closing saidbypass and formed with a channel forming a part of said second-mentionedpassa'geway, and a valve carried by'said relief valve member forpreventing movement of fluid from beneath said piston to said pumpchamber.

8. In a hydraulic jack, apiston cylinder, a piston therein, a reservoir,a passageway leading from said piston cylinder, a passageway leadingfrom said reservoir, a,, pump barrel secured on said jack and havln apump chamber, a wall of said chamber belng provided with an aperture,means extending through said aperture and provided with a bore the outerend of which communicates with one of said passageways, with aperipheral recess covered by the said wall, with a valve for closing theouter end of said bore, and'with corridors between said rewith one ofsaid passageways, with a peripheral recess covered by the said wall witha .valve for closing the outer end of said bore, and with corridorsbetweensaid recess and said bore, a channel in the side wall of saidpump barrel communicating with the other of said passageways and withsaid recess, a valve normally closing said channel, and a by-passconnecting sa1d passageways and comprising a second channel in sand pumpbarrel and an exterior peripheral recess 1n said pump barrel, a reliefvalve nor mally closing said'by-passwand formed with a channel forming apart of said second mentioned passageway, said first mentioned gzlvebeing carried by said relief valve mem- In testimony whereof I afiix mysignature.

CHARLES F. BACON.

